I'm posting on behalf of my mum who asked if I would post to see if anyone can help identify a possible cause for these three very similar deaths. Three rats from the same group have died over the course of three weeks, all in exactly the same way; all were previously healthy and showed no signs of illness before death.

The first death was Logan. He was a good sized boy at around 600g, completely healthy and had no current illness at the time of death. He was just short of 17months old when he passed. He was found lying unconscious in his cage, still breathing and heart beating but otherwise totally lifeless and didn't seem to be suffering in anyway. He then suffered a massive fit and died 5hrs after being found. As there is a history of strokes within his brothers from the same litter, it was suspected he had a massive stroke which rendered him unconscious and his brain slowly died as a result of the stroke and he later died.

Then a week later Amelia died. She had a residual head tilt and was 2yrs old at the very least; she was beginning to show her age but was otherwise healthy. She was also found unconscious in her cage in the same way was Logan. She suffered a couple of little fits, in between which she returned to her peaceful, unconscious state, and then had a massive fit and died 3hrs after she was found. After this death, suspecting the possibility of something contagious, the cage was deep cleaned, all hammocks washed at 60, wooden toys thrown out and all plastic toys soaked in disinfectant.

After Amelia's death, this left one rat, Madeline, from the group on her own and because of the suspicion of something contagious, I advised mum to quarantine her for two weeks, which she did and that finished yesterday; Mum introduced her to another group which was very successful. Maddy is around 2yrs old and has a slight residual head tilt but has always been the brightest of her group and very very healthy. This evening Mum found Maddy unconscious, breathing and heart beating, just like Logan and Amelia. The last I knew Maddy was still alive but totally unresponsive; if by any chance she's still here in the morning Mum will take her to be PTS but she doesn't think she'll make it

There is obviously a contagious element to this but what on earth could it be?! Like I said, all the rats were healthy and had no signs of illness prior to their collapse; Amelia had even been free ranged just two hours before her collapse! What is confusing me is that none of mums other rats are ill at all; she has three other groups that live in close proximity to the effected rats and no one else has been ill. So there seems to be a contagious element but there needs to be direct contact with any effected rat. I was thinking perhaps a meningitis type infection but don't know how likely that is in rats? Mum is now obviously concerned about the group Maddy has recently been introduced to as well; are there any steps that can be taken to try and prevent them from becoming ill?

Unfortunately a PM isn't possible due to the cost and the relative inexperience of our vets. I have suggested allowing someone experienced to do one but mum wasn't happy to do so. I'm not sure if an infection would show up on a PM? I don't know a lot about them so I could be wrong.

Are you sure there are no (however small) symptoms your mum is missing?

The "aftermath" of it (the rat being unconscious) is very similar to what happened with Danny and Arnie (viewtopic.php?f=38&t=11882). The symptoms were very small, really and were only really obvious to me because I was looking for symptoms because of the abscess. With Danny, he just fell into an almost coma like state and never responded to anything. With Arnie, he was the same however he would every so often just up and clean himself, but then fall back down. It was almost like instinct rather than him wanting to cleaning himself (as other than that, he never responded to anything and wouldn't swallow water or food).

With Danny, it was exactly like what happened with your Maddy, with anti-biotics both Danny and Arnie reacted well to it for a few hours. With Danny, he was okay with some minor symptoms when I went to bed, and he was unconscious less than 10 hours later. Arnie fought whatever it was, but Danny died very quickly after symptoms came on.

Thank you Anthony, I shall pass the information on to mum. I wonder if it's worth getting the rats Maddy has been in contact with on a high dose of baytril asap?

Obviously I haven't seem the rats myself prior to death but mum reports no sign of anything wrong with them at all prior to collapse and death. And she's been watching Maddy like a hawk these two weeks before she intro'd her and there has not been a single sign of anything.

It's just very bizarre. The fact that none of the other rats living close to the group have been affected confuses things!

My best guess is it is a brain infection of some sort. I know it's been decided it's not an option here, but the only real way of telling would be a PM. It wouldn't necessarily pick up an infection, but I imagine even a bulk PM would show inflammation of the brain tissue, and the type and location of that could be informative - e.g. meningitis is inflamnation of tissue around the brain.

I'm concerned that this has happened to both your Mum and Anthony in a fairly short space of time. Were any of the rats in either case at shows / rat meets / even the vet etc in the weeks before this happened? It may all be a coincidence, but I think as a community people need to be aware that there appears to be something of this nature out there.

There's no way that Anthony and Mum could have met; she hasn't had any newcomers in quite a while and she doesn't attend rat shows or meets. And Anthony lives a considerable distance from us so they won't have crossed paths and a vet or anything.

I would just like to say for those concerned about the rescue and my rats, I haven't been at my mums for 2wks now and when I was there I made sure I didn't handle any rats at all and as soon as I got home my clothes were washed and I showered. I thought it was unlikely I would pick anything up as it seems direct rat-to-rat contact is needed but I took the precaution anyway. There are no rats with illnesses of this type here at the moment.

Would prophylactic antibiotics be beneficial for the remaining rats Maddy has had contact with?

I wasn't so much thinking that your mum and Anthony could have come into direct contact, so much as either could have come into contact with a common factor - which could be several steps removed from both of them. That's why I asked about vets visits etc - is there anywhere outside the house they could have picked this up? It may well be that it is two completely different things - although the fact they are both contagious, rapidly fatal and essentially neurological is concerning.

It's impossible to say whether prophylactic antibiotics would be actually beneficial without knowing what the problem was - if it was viral they will have no effect, and even if it's bacterial then we don't know what antibiotic is needed. That said, given it is so rapidly fatal, with no symptoms to catch, I'd probably try it as a precaution.

neotoma wrote:I wasn't so much thinking that your mum and Anthony could have come into direct contact, so much as either could have come into contact with a common factor - which could be several steps removed from both of them. That's why I asked about vets visits etc - is there anywhere outside the house they could have picked this up? It may well be that it is two completely different things - although the fact they are both contagious, rapidly fatal and essentially neurological is concerning.

It's impossible to say whether prophylactic antibiotics would be actually beneficial without knowing what the problem was - if it was viral they will have no effect, and even if it's bacterial then we don't know what antibiotic is needed. That said, given it is so rapidly fatal, with no symptoms to catch, I'd probably try it as a precaution.

NMT100 and i have just had the same conversation.

neotoma wrote:My best guess is it is a brain infection of some sort

We were wondering about the potential of something from a new lot of food, or more possibly something like the ratty equivalent of Tic born encephalistis (which takes a while to manifest), from the wild (having gone walking and brought in on clothes, dogs, cats etc) or even from a new lot of bedding? Mites or otherwise in bedding could carry a new virus?

Is the new syndrome present in any other species at the moment? Could have been transmitted at vets from other animals who may even just be carriers?

?Brought in on exotic fruit for humans etc

Prophylactic antibiotics may help if bacterial but only if, obviously and would have to be fairly wide spectrum (i doubt this though). Doxy does have a slight effect of reducing any inflamation so may help reduce brain swelling (of the meningies).

I'm just thinking of the london dungeon abscess rats here. Only the original rats and cage-mates had the abscesses, it never spread to other communities so wasn't contageous in the traditional sense. It seemed to spread through eating the faeces of affected rats. If it was a food, wouldn't all your mum's groups show signs of it? Ditto for bedding and insect bites. Perhaps it only affects rats to this extent if they have a genetic weakness? Certainly is a puzzler. I'm sorry for anyone who's lost rats to this, it sounds like a truly awful thing to have to witness.

ETA; for some reason I got to thinking about the mad cow disease outbreak, I was trying to work out what could stay in the system for a long time and cause such a rapid demise in latter stages without being airborne. This may be something to think about, but I also may be completely wrong. Feel free to shoot me down, it would be obvious if it was this from a PM.

Last edited by Exogenesis on Sat Aug 18, 2012 10:37 am, edited 1 time in total.

This sounds so much like the infection I had in a group of five boys, all brothers. They all succumbed and died one by one, all had fits, fell in to comas and passed. My vet diagnosed them with viral menengitis. The rest of the rats in the same air space were treated with a blanket course of abs as a last desperate attempt at saving them, abs do not do anything for virus infections. I think the vet just advised that so I felt as if I was doing something for them. I had been no where with rats in the previous month, no new rats in, nothing. All my other rats were fine and to date I have not had a repeat of this dreadful disease. I do hope that this will be the case for your mum.

Rats have whiskers so sensitive that they can fit into the smallest cracks of a broken heart.

Not an epidemiologist, but I've prodded a good vet to see if he has any ideas.

My hunch in Anthony's case was bacterial meningitis, because the symptoms were neurological (suggesting a brain infection), but he said at the time that both rats got a blackened patch on their skin shortly before death, which suggested septiceamia. I am a vey long way from being an expert on this though.

Thanks to everyone for all the replies and information, it is much appreciated.

To answer the points that have been raised:

-None of the effected rats left the home for any reason in the weeks prior to their death.
-Mum has been to the vet for other animals but hasn't been to any rat meets or anywhere else rats could be.
-mum also has rabbits, guinea pigs, chinchilla, gerbils, hamsters and a cat in her home. No other animal has had an illness of this type during this time
-The cat is an indoor cat and has never been outside. He is regularly treated for fleas, worms and parasites because mum is paranoid about that sort of thing!
-Mum orders all food and bedding for the rats from ratrations- if there was something coming in on that I think more people would have experienced this. She buys bedding for the other animals from the local farm shop but this is stores separately from the rat stuff.

I have thought of something else that may be relevant. I didn't remember it last night but it came to me this morning. Logan's brother, Arthur, died less than a week after he arrived at mums. We never found out why, mum just found him dead in the cage one morning. This was back in Feb/March. Is it possible that Arthur's death is connected and the boys themselves are the source?

I think I'd be inclined to follow exogenesis' theory of it being some sort of direct contact with the effected rats just because there are other groups of rats living close by with the same food and bedding from the same source.

I suppose it is possible that the boys are the source (certainly there isn't a source that stands out, unless any wild mice could have got in the house, or it is something humans can carry but don't get).

One entirely random possibility that occured to me is an abcess on the brain - if they carry the bugs, but they sucumb to them at different rates. However, I've no idea if that actually makes medical sense in this context in terms of symptoms etc.